Temperatures are rising and beach season is in full swing — which means consumers are stocking up on sunscreen.
But it's not as easy as S-P-F.
Store shelves are loaded with sprays and lotions with SPFs, or sun protection factors, approaching triple digits. Some protect against sunburn but not long-term skin damage. Then there's recent research that found all but a sliver of sunscreen products less effective than manufacturers claim — and even potentially dangerous.
And with all that confounding consumers, medical experts worry that claims of high-level protection could lull consumers into a false sense of security or fears about safety could deter them from using sunscreen altogether.
"Basically, having any kind of protection is better than no protection," said Dr. Ali Hendi, a board-certified dermatologist, surgeon and skin cancer expert in Chevy Chase.
SPF is a measure of protection against UVB rays, which cause burns. If your unprotected skin burns after 10 minutes of exposure, an SPF of 30 that's recommended by many experts would theoretically increase your protection to about 300 minutes. The protection could be shorter-lived, though, as sunscreens become less effective as they rub off with activity, according to the American Academy of Dermatology.
In a study released last month, the Environmental Working Group, a nonprofit public health advocacy group, recommended only 8 percent of 500 sunscreen products it evaluated for effectiveness and safety.
While one in six products now features SPFs higher than 50, EWG research analyst Nneka Leiba contends that most people never put on enough to reach the intended protection level. Nor, she says, do most people reapply every two hours as recommended. The amount of sunscreen manufacturers use in testing is four to five times what people normally use, Leiba added.
"They have a false sense of security of how much protection they're getting and stay out in the sun a lot longer," Leiba said. Her recommendation to consumers on the amount of sunscreen to apply: "Just use two or three times what you think would be enough."
The industry defends the labeling on sunscreens and says the EWG report had serious shortcomings because of questionable scientific methodology.
"The [manufacturers'] testing and SPF number takes into account that real-life use," said Farah K. Ahmed, chair of the sunscreen task force for the Personal Care Products Council, which represents the manufacturers.
Beyond the debate over sunburn protection is the sometimes-overlooked need to also protect against UVA rays, which account for the vast majority of UV radiation to which people are exposed and can lead to premature wrinkles and age spots.
Consumer Reports, in the July issue of its magazine, tested sunscreen sprays and how well they provide what is called "broad spectrum" coverage against both UVA and UVB rays.
The nation's annual toll of skin cancer is more than 1 million cases and more than 11,000 deaths from the disease. UV radiation, much of it from the sun, is the biggest cause of the condition, according the American Cancer Society.
The cancer rate, in addition to concerns about ingredients and labeling, has prompted calls for the federal government to develop better rules to govern the sunscreen industry.
Without better federal oversight, manufacturers "have a long rope with which they can run," said Leiba, the EWG research analyst.
Sunscreens are currently regulated by the Food and Drug Administration as an over-the-counter drug, which covers ingredients, doses, formulas and labeling. New rules involving testing and labeling about UVA protection are expected to be approved in October; manufacturers would have a year to comply.
FDA spokeswoman Shelly Burgess said a 1993 FDA rule never went into effect because it only addressed UVB rays, not UVA rays. And a rule proposed in 2007 that covered UVA exposure generated a lengthy public debate. "It's just taken longer than originally anticipated and more FDA resources to get that done," she said.
Last month's EWG report involves an ingredient designed to slow skin's aging process — a vitamin A derivative called retinyl palmitate — that is found in many sunscreen products. The EWG research points to an FDA study that indicates the ingredient can promote the growth of cancerous tumors.
That drew protests from the Skin Cancer Foundation that the EWG report could discourage people from using sunscreen altogether. That organization's photobiology committee reviewed the data and determined that retinyl palmitate is not a photocarcinogen, according to a statement on its website.
Beyond the debate over sunscreen's science and regulations, consumers should still defer to common sense by wearing protective clothing and avoiding peak sun hours, medical experts advise.